A review of fertilizer, lime and organic manure use on farm crops in Great Britain from 1983 to 1987

Abstract. In 1983, an annual Survey of Fertiliser Practice in England and Wales was extended to Scotland, to provide comprehensive information on inorganic fertilizer, lime and also organic manure use in mainland Britain. It was based on an annual sample of about 1500 farms, selected from the Agricultural Census and stratified by farm type and size. Results from the first fifteen years (1983–97) show that fertilizer nitrogen (N) rates on both tillage crops and grassland peaked at 157 and 132 kg ha^–1, respectively, in the mid 1980s and subsequently decreased by c.10%. The majority of N was applied in straight form (without P or K) to tillage crops and in compound form (containing two or more nutrients e.g. NPK; NK) to grassland. Total N use on cereals showed little change but autumn‐applied N decreased on both winter cereals and winter oilseed rape. Total N rates decreased on oilseed rape and, to a smaller extent, on maincrop potatoes and sugarbeet. Between 1983–87 and 1993–97, mean phosphate (P₂O₅) rates declined by almost 10% on both tillage crops (from 58 to 53 kg ha^–1) and on grassland (from 25 to 23kg ha^–1). The corresponding mean potash (K₂O) rates decreased slightly on both tillage crops (from 64 to 62 kg ha^–1), and on grassland (from 32 to 31 kg ha^–1), although annual usage was more variable on grassland. Sulphur use increased appreciably on cereal and oilseed rape crops between 1993, when S data were first recorded in the survey, and 1997 when 13% and 30%, respectively, of these crop areas received S‐fertilizer. However, on grassland, S use remained very low. Average lime use increased on both tillage crops and grassland between the mid 1980s and mid 1990s, from 10 to 12% and 4 to 7% of the total area, respectively. The proportion of land receiving organic manures remained at c. 16% for tillage cropping but increased slightly for grassland, from a mean of 40% in 1983–87 to 44% in 1993–97. Manures were applied throughout the year but about half the applications to tillage land, and a quarter of those to grassland, were made in autumn when the risk of subsequent nitrate leaching loss is greatest.     

Vergleichende Betrachtung von Verfahren zur Auswertung von Nährstoffsteigerungsversuchen am Beispiel Phosphor

Comparison of two procedures to evaluate phosphate‐fertilizing field trials Growth response of agricultural crops to different input levels (e.g., fertilizer rates) can be described by the “law of diminishing increments”, which has been formulated mathematically amongst others by Mitscherlich (1928) and von Boguslawski and Schneider (1962, 1963, 1964). In the present paper, the economically optimal phosphate‐fertilizer requirements in 43 long‐term phosphate (P)‐fertilization experiments were calculated using equations on the basis of the yield functions of Mitscherlich or von Boguslawski and Schneider, respectively. For three field trials with linear or disproportionately high yield responses on P fertilization, none of the two procedures could be used. The same held for four trials with maximum yields already appearing at the first fertilization level. Similar P‐fertilization optima were calculated for 36 trials following the “law of diminishing increments”, resulting in a highly significant correlation (R² = 0.946) between both procedures. The correlation coefficients between the phosphate balance at the calculated optimum profitability and CAL‐P content in the soils at trial start were R² = 0.70 (Mitscherlich, 1928) and R² = 0.65 (von Boguslawski and Schneider, 1962, 1963, 1964), respectively. An optimal soil P content of 8–10 mg CAL‐P (100 g soil)^–1 was deduced. Both methods are applicable to calculate the optimum phosphate‐fertilizer requirement if yield effects due to P fertilization follow the “law of diminishing increments” and the increments of fertilization levels in each trial are established in a way that diminishing yield increments can be expected.     

Effects of green manure and coral lime on corn growth and chemical properties of an acid Oxisol in Western Samoa

Effects of local green manure (GM) and lime on soil productivity in a low-input agricultural system were evaluated by growing three successive crops of sweet corn (Zea mays) on an acid Oxisol (Typic acrorthox, Togitogiga series) in Western Samoa. The soil was amended with coral lime at 0, 5, and 10Mgha^–1 and with cowpea GM at 0, 7.5, and 15Mgha^–1. Commercial NPK fertilizers at 50kgha^–1 each of N, P, and K were included for comparison. The amendments were applied only once prior to planting of the first crop. Response parameters measured included nutrient composition of leaves at tasseling and grain yield of each crop, and selected soil chemical properties at each planting. Yields of the first crop were nearly tripled with GM additions and doubled with lime additions. Such yield increases were caused mainly by better K nutrition and to a lesser extent by enhanced P nutrition. Yields of subsequent crops were much lower than those of the first, and the declines were much steeper for the GM treatments than for the lime treatments. Thus, the enhancement effect on K nutrition did not last beyond one crop. Poor growth of the second and third crops was caused by K deficiency; probably coupled with Mn toxicity. Significant yield reductions were found when Mn-to-K ratios in leaves exceeded 0.010. As for effects on soil, soil pH was increased significantly by lime but only slightly by GM. Given the variable charge property of this Oxisol, each unit pH increase corresponds to a cation exchange capacity (CEC) increase of 5cmol_ckg^–1. Having greater CEC, the amended soil retained K more effectively, thereby causing yield increases, especially of the first corn crop, which required at least 0.75cmol_ckg^–1 of exchangeable soil K or 7% of CEC for adequate growth. Received: 15 April 1996     

Fungal solubilization of rock phosphate is enhanced by forming fungal-rhizobial biofilms

Biosolubilization of rock phosphate (RP) using a Penicillium spp., an Aspergillus spp., Pleurotus ostreatus, Bradyrhizobium elkanii SEMIA 5019 and their fungal-rhizobial biofilms was investigated. Eppawala Rock Phosphate (ERP, total P concentration 17.6%), a RP from a deposit in Sri Lanka was used. Penicillium spp.-B elkanii SEMIA 5019 biofilm released the highest amount of P from the ERP with the highest P release-to-P uptake ratio. The P release of Penicillium spp. alone was significantly lower than that of its biofilm. Similarly, P. ostreatus-B. elkanii SEMIA 5019 biofilm showed a higher P release than P. ostreatus alone. However, P. ostreatus alone or its biofilm showed lower P release-to-P uptake ratios indicating relatively higher P uptake compared to the P release. The Aspergillus spp., showed a moderate P release. Large bradyrhizobial cell clusters attached to the mycelial mat of Penicillium spp. and P. ostreatus were observed under light microscope after 12 and 25 days of incubation, respectively. The present study, identified an effective method of fungal-rhizobial biofilm mediated solubilization of RP.     

根-土界面区域磷酸盐的分布和移动: Ⅲ. 动力学

The depletion rate of phosphate in the soil-root interface zone increased along with growth and phosphate uptske of wheat or maize,which indicated that the phosphate distribution in soil near the root surface agreed well with the phosphate movement in rhizosphere and phosphate uptake by plant,The relative accumulation zone of phosphate within 0.5mm apart from the root surface developed at the 15th day or so after cultivating wheat or maize since the root phosphate secretion increased gradually in this stage.The phosphate distribution in the soil-root interface zone against the growing time(t)and the distance from the root plane(x) could be described by the non-linear regression equation with the third powers of x and t.     

小麦缺铜不实与花淀粉积累的关系

本文就缺铜小麦“穗而不实”原因作了探讨，初步认为与植株总体糖水平下降、茎基部缺乏糖分积累和抽穗扬花期糖分向穗部转移滞缓不畅有关。     

盐胁迫下转甜菜碱醛脱氢酶基因水稻幼苗耐盐生理的研究

在NaCl浓度0，3．0，5．0，7．0g／L下，对转甜菜碱醛脱氢酶(BADH)基因水稻的两个品系51—22，52—7及其受体亲本中花8号进行幼苗耐盐性试验。结果表明：转BADH基因水稻比其受体亲本耐盐性强，在高NaCl浓度(5．0，7．0g／L)胁迫下，甜菜碱醛脱氢酶基因可以提高盐胁迫下水稻幼苗过氧化氢酶(CAT)活性，提高根系活力和叶绿素含量，稳定细胞膜的透性，降低植株体内Na^ 的积累，从而减轻幼苗受盐害的程度。盐胁迫下水稻幼苗的CAT活性、SNa^ ／K^ 、叶Na^ ／K^ 、叶绿素含量是影响幼苗生长的主要生理指标。     

Chromosomal location of genes controlling 6-phosphogluconate dehydrogenase,glucose-6-phosphate dehydrogenase and glutamate dehydrogenase isozymes in cultivated rye

Summary The 6-phosphogluconate dehydrogenase (6-PGD), glucose-6-phosphate dehydrogenase (G-6-PD) and glutamate dehydrogenase (GDH) zymogram phenotypes of wheat, rye and their aneuploid derivates were determined. At least three genes involved in the production of 6-PGD isozymes were located on chromosome arms 4RL, 6RL and 2RL of Imperial rye, King II rye and Dakold rye. Evidence was obtained that at least one gene located on chromosome arm 5RS controls G-6-PD isozyme activities in these varieties of rye and one gene involved in the production of GDH isozymes was located on chromosome arm 2RS of Imperial, King II and Dakold rye. The results indicate that the 6-PGD isozymes exist as dimers and monomers. No possible structure of the G-6-PD and GDH could be determined.     

Short Communication A low morphine-containing accession of Papaver somniferum suitable for seed production*

A total of 140 Indian accessions of Papaver somniferum were raised under the subtropical conditions of Lucknow, India. They were screened for major alkaloids present in the capsules and peduncles, using a TLC-densitometry procedure. An accession containing the narcotic alkaloid morphine at as low a concentration as 0.05% in its capsules has been identified. The accession has good agronomic traits.     

QTL mapping of phosphorus deficiency tolerance in soybean (Glycine max L. Merr.)

Phosphorus (P) deficiency is a major abiotic stress that limits plant growth and crop productivity throughout the world. In the present study, 184 recombinant inbred line (RIL) families developed from soybean varieties Kefeng No. 1 and Nanong 1138-2 were used to identify quantitative trait loci (QTL) associated with P deficiency tolerance. Seven traits of plant height (HT), weight of fresh shoot (FSW), weight of fresh root (FRW), weight of dry root (DRW), length of main root (RL), phosphorus content in leaf (LP), phosphorus content in root (RP), were used as parameters to assess the phosphorus deficiency tolerance. The QTL mapping for the seven traits was performed using the program WinQTLCart. Seven QTLs were detected and mapped on two linkage groups for three traits of weight of fresh shoot, phosphorus contents in leaf and in root. The QTLs that had LOD scores more than three were detected for all of the three traits above. Most of the QTLs explained more than 10% of the total variation. The two QTLs for phosphorus content in leaf explained more than 20% of the total variation, respectively. Five QTLs were mapped on linkage group F2, and two on linkage F1. It was suggested that the genes related to phosphorus deficiency tolerance located on linkage group F in soybean.Contributed equally to this work.